Yoke construction



July 14, 1925.

L. RICHARDSON YOKE CONSTRUCTION Filed Aug. 28. 1924 AHHHHIH IApplication filed August 28, 1924.

Patented July 14, 1925.

UNITED\ STATES MrsnfoFFioi- LAWRENCE RICHARDSON, OF CHICAG-O, ILLINOIS.

YOKE CONSTRUCTION.

T 0 tull "whom z't may camera:

Be it known that I, LAWRENCE RICHARD- soN, a citizen of the UnitedStates, residing at Chicago, in the County of Cook and State ofIllinois; have invented certain new and useful lmprovements in YokeConstructions, of which the following is a specification.

This invention relates to a railway car draft yoke.

In the ordinary integrally formed draft yoke the weakest points at therear end thereof are at the inner points of joining between the draftarms and the rear connecing member. When a car is subjected to a jerk,the draft arms are subjected to tension which is fairly uniformlydistributed in said arms, but the jerk is finally resisted by the draftgear or other appliance, which causes the load to be delivered at thecritical points in question. A beam action results with the defiectiontaking place in the center of the rear connectng member. This defiectionincreases the tension stress at the two high tension points.

One object of the invention is to minimize the excessive tensionstresses at the critical points in question in a simple and eflicientmanner.

Another object is to provide a simple, durable and reliable draft yokeConstruction in which the tension stresses at the inner points ofjoining between the draft arms and rearconnecting member are appreciablyreduced or neutralized.

These and other objeets are accomplished by means of the yokeConstruction disclosed on the accompanying sheet of drawings, in which--Figure 1 is a side elevation of a railway car draft yoke embodying myinvention;

Figure 2 is a top plan View thereof; and,

Figure 3 is a side elevation of the general type of draft yoke in commonuse.

Referring first to Figure 3, it will be noted that the usual integraltype` of draft yoke includes upper and lower arms 10 and ll,respectively, which are connected to each other by a rear connectingmember 12. In this particular instance the front ends of the arms areconnected by a strap 13, one

Serial No. '734,590.

at each side. It will be noted that the arms 10 and 11 in Figure 3 arestraight throughout their( lengths rearwardly from a point not fardistant from the front ends thereof. As mentioned hereinabove, when acar is subjected to a jerk, excessively high tension stressesareconcentrated at the inner connect-ing points of the arms 10 and 11 andthe rear connecting member 12, the Stress being increased as the resultof a beam action in the cross member 12 due to engagement With the usualdraft gear member 15.

To overcome the excessive tension at the points in question, in themanufacture of yokes, the draft arms 16 and 17 respectively, as shown inFigure 1 are bowed outof the draft arms 16 and 17 will have a tendencyto straighten, causing, in so far as this straightening action isconcerned, aconcentration of compressive force or action at the criticalpoints 19, thereby reducing the total amount of tension at such points.In this way the excessively high tension stresses at the criticalpoints19 are greatly reduced, thereby relatively increasng the strength of theyoke.

I claim:

1. A railway draft yoke comprising draft arms and a rear connectingmember a ll formed in a' single integral piece Wherein under jerky draftconditions relatively high tension stresses tend to concentrate at theinner points of joining between said draft arms and rea-r member, saidarms adjacent said rear member and forwardly of said points of joiningbeing bowed outwardly to reduce the tension stresses at saidpoints. r

2. A railway car draft yoke comprising draft arms and a rear connectingmember all formed in a single integral piece wherein underjerky draftconditions relatively high tension stresses tend to concentrate at theinner points of joining 'between said draft arms and rear member, saidarms interrsaaazmediate their ends being bowed to reduce the tensionstresses at said points.

3. A railway car draft yoke eomprising draft arms and a rear connectionmember all formed in asingle integral piece Wherein under jerkydrafteonditions relatively high tension stresses tend to conoentrate atthe inner points of joining between said draft? arms and real member,said arms forwardly of said high tension points being ,boWed 10outwardly to reduce tension stresses at said points.

Signed at Chicago, Illinos, this 22nd day oi August, 1924.. 4

LAVVBENCE RICHARDSON.

